FR2951735A1 - METHOD FOR CONVERTING RESIDUE INCLUDING MOBILE BED TECHNOLOGY AND BOILING BED TECHNOLOGY - Google Patents

Abstract

The invention relates to a process for converting heavy carbon fractions having an initial boiling point of at least 300 ° C. into yieldable lighter products, said process comprising a passage of said feedstock in a hydrorefining reaction zone comprising at least a moving bed reactor, and the passage of at least a portion of the effluent from step a) in a hydroconversion reaction zone comprising at least one triphasic reactor, in the presence of hydrogen, said reactor containing at least minus a hydroconversion catalyst operating as a bubbling bed, with an upward flow of liquid and gas and comprising at least one means for withdrawing said catalyst from said reactor and at least one fresh catalyst booster means in said reactor, in conditions to obtain a reduced Conradson Carbon content liquid filler, metals, sulfur and nitrogen.

Description

The invention relates to the refining and the conversion of heavy carbon fractions optionally containing, among other things, sulfur-containing impurities (for example having an initial boiling point of at least 300 ° C., such as a petroleum residue, derivatives derived from biomass , coal) in lighter products, recoverable as fuels. It relates more particularly to a process for converting at least partly a hydrocarbon feedstock, and in particular a petroleum residue into recoverable lighter products while improving the properties and stability of unconverted heavy residues.

More specifically, the carbonaceous feedstocks concerned are heavy hydrocarbon (petroleum) feedstocks such as petroleum residues, crude oils, crude heading oils, deasphalted oils, deasphalting asphalts, derivatives of petroleum conversion processes (ex: HCO, FCC slurry, GO heavyNGO coking, visbreaking or similar thermal process, etc ....), bituminous sands or their derivatives, bituminous schists or their derivatives, or non-petroleum feedstocks such as gaseous derivatives and / or liquids (containing no or few solids) of the thermal conversion (with or without catalyst and with or without hydrogen) of coals, biomass or industrial waste such as recycled polymers More generally, we will group here under the term "hydrocarbon heavy load" which is treated in the context of the present invention, the atmospheric residue of distillation say coast, obtained by atmospheric and vacuum distillation of a crude oil. These feedstocks are usually hydrocarbon fractions having a sulfur content of at least 0.5%, preferably at least 1% and preferably at least 2% by weight, a carbon content Conradson d at least 3% by weight and preferably at least 10% by weight, a metal content of at least 20 ppm and preferably at least 100 ppm and an initial boiling point of at least 300 ° C preferably at least 360 ° C and preferably at least 370 ° C and a final boiling temperature of at least 500 ° C, preferably at least 550 ° C, preferably at least 500 ° C. above 600 ° C and very preferably 700 ° C. Preferably, the charges that are treated in the context of the present invention are atmospheric residues corresponding to a 380 ° C + cut, vacuum residues corresponding to a 560 ° C + cut and deasphalted oils (DAO) corresponding to cut 560 ° C + lighter.

The charges resulting from thermal conversion, with or without a catalyst, and with or without hydrogen, contain, for their part, generally less than 50% of product distilling above 350 ° C. and very little or no vanadium and / or or Nickel, few asphaltenes, that is to say a content advantageously less than 10% by weight and preferably less than 5% by weight of asphaltenes with heptane, and preferably less than 2% by weight of asphaltenes ) but they contain oxygenated molecules with an oxygen content advantageously between 0.5 and 50% by weight; predominantly basic nitrogenous molecules with a nitrogen content advantageously between 0.2 and 2% by weight and aromatic molecules difficult to convert in fixed bed hydrotreating / hydroconversion processes, as well as metals harmful for catalysts such as alkali metals (Na, Ca, K for example) or silicon.

One of the objectives of the invention is to provide a process for the conversion of carbonaceous feedstock and preferably heavy hydrocarbon fractions having an initial boiling point of at least 300 ° C. into lighter, recoverable products, incorporating a technology that can be used. mobile and boiling bed technology, said method for maximizing the refining of the charge while increasing the conversion of the charge. STATE OF THE ART On a worldwide level, the use of fixed-bed reactors remains much greater than that of bubbling-bed reactors. Fixed bed systems are mainly used for the treatment of naphthas, middle distillates, atmospheric and vacuum gas oils and atmospheric residues and vacuum residues. The advantage of fixed bed processes is that high refining performance is obtained thanks to the high catalytic efficiency of fixed beds. On the other hand, above a certain metal content of the feedstock (for example 100 to 150 ppm), although using the best catalytic systems, it can be seen that the performance but above all the duration of operation of these processes become insufficient: the reactors are quickly loaded with metals and thus deactivate. To compensate for this deactivation, the temperatures are increased, which favors the formation of coke and the increase in pressure drops. It follows that we are led to stop the unit at least every 3 to 6 months to replace the first deactivated or clogged catalytic beds, this operation can last up to 3 weeks, which reduces by the same factor operative of the unit. Thus, when the load becomes heavier, has a higher impurity level or requires more severe conversion levels, the fixed bed system becomes less efficient and less cost effective. In this case, ebullated reaction systems are better suited for the treatment. In general, ebullated bed reactors are used to treat charge streams consisting of heavy residues, particularly those with high levels of metals and metals. Conradson residues. In the bubbling bed process, concurrent streams of liquids, or slurries of liquids and solids, and gas are passed over a vertical elongated triasic fluidized catalytic bed. The catalyst is fluidized and completely mixed by the upward flowing liquid streams. The ebullated bed process has a commercial application in the conversion and upgrading of heavy liquid hydrocarbons and the conversion of coal into synthetic oils. The bubbling bed reactor and the related method are generally described in US Pat. No. 25,770 to Johanson, incorporated herein by reference. A mixture of hydrocarbon liquid and hydrogen is passed upwardly over a bed of catalytic particles at a rate such that the particles are subjected to forced random movement as the liquid and gas flow through the bed from bottom to top. . The movement of the catalytic bed is controlled by a flow of recycle liquid such that, in a steady state, the catalyst mass does not rise above a definable level in the reactor. Vapors and the hydrogenated liquid pass through the upper level of the catalyst particle bed to reach a substantially catalyst-free zone, and are removed from the upper portion of the reactor. Bubbling bed reactors generally operate at relatively high temperatures and pressures to treat these heavy loads. Bubbling bed technologies use supported catalysts in the form of extrudates whose diameter is of the order of 1 mm. The catalysts remain inside the reactors and are not evacuated with the products. The temperature levels are high in order to obtain high conversions while minimizing the amounts of catalysts used.

Boiling bed technology generally uses high temperature levels to minimize catalyst quantities and requires a low hydrogen coverage rate. The catalytic activity can be kept constant by in-line catalyst replacement, so there is no need to increase the reaction temperatures along the operating cycle. The recycling of the liquid allows the bubbling of the catalyst bed, the maintenance of a uniform temperature in the reactor and the stabilization of the catalytic bed.

Bubbling bed technology is therefore generally used to obtain long operating cycles of the unit and in order to maximize the level of conversion of the load at the expense of the objective of refining products. The use of a perfectly stirred reactor allows the replacement of the catalyst while keeping the unit in operation but causes degradation of the refining performance compared to the performance obtained using the fixed bed reactor.

Mobile bed technology is also used for the hydrotreating of petroleum residues.

It is particularly suitable for the treatment of metal-rich fillers and allows capture. For example, a process scheme may include one or more moving bed reactors in series loaded with substantially hydrodemetallization catalysts followed by one or more fixed bed reactors in series containing essentially hydrodemetallization and hydrodisulfurization catalysts. The catalysts used in the spent moving bed reactor are advantageously withdrawn at the bottom of said reactor. Said spent catalysts are saturated with metals (Ni + V), whereas in the case of fixed beds, only the upper part of the catalytic bed is saturated with metals. This results in less catalyst consumption for moving bed reactors, especially in the case of countercurrent moving bed reactors. (Reynolds B.E., Bachtel R.W., Yagi K. (1992) Chevron's onstream replacement catalyst (OCR), NPRA meeting New Orleans)

Said mobile bed technology uses reactors in which a device allows the semi-continuous renewal of the catalyst in the reactor which keeps the catalytic activity constant. Mobile bed technology typically uses temperature levels equivalent to fixed bed technology but lower than bubbling bed technology. On the other hand, as for the fixed bed technology, it is necessary to control the reaction exotherms in each reactor by quench injection, usually gas, but it is not necessary to increase the reaction temperatures along the reaction cycle. operation, said temperatures being identical at the beginning and at the end. Indeed, the mobile bed technology allows to operate continuously by withdrawing the spent catalyst and its replacement with new catalyst. However, these catalyst replacement operations can produce fines entrainment which can be deposited on the fixed bed catalysts located in downstream causing an increase in pressure drop. The main advantage of the moving bed is its ability to deal with long cycle times loads with high metal content. Catalyst consumption is lower than for other processes. The yields and qualities of products are similar to those of fixed beds for the same operating conditions.

The mobile bed technology thus makes it possible to maximize the refining of the charges used and in particular hydrodenitrogenation, hydrodesulphurization, desasphalogenization and especially extensive demetallation, but while maintaining a low conversion of the charge.

The implementation of a process for the conversion of carbonaceous feedstock and preferably of heavy hydrocarbon fractions having an initial boiling point of at least 300 ° C. into recoverable lighter products, incorporating a mobile bed technology and a technology bubbling bed, therefore has obvious synergies in performance levels that make it possible to achieve goals otherwise unattainable by the two technologies taken separately. Indeed, the method according to the invention makes it possible to maximize the refining of the feedstock by using at least one moving bed reactor, said moving bed being placed upstream of at least one bubbling bed reactor allowing increase the conversion of the load.

DESCRIPTION OF THE INVENTION The present invention therefore describes a process for converting carbonaceous feedstock and preferably heavy hydrocarbon fractions having an initial boiling point of at least 300 ° C. into lighter, recoverable products, said process having the following characteristics: following steps: a) passage of said feedstock in a hydrorefining reaction zone comprising at least one moving bed reactor comprising at least one catalytic bed of hydrorefining catalyst and at least one means for withdrawing said catalyst from said reactor and at least one fresh catalyst booster means in said reactor, said catalyst circulating by gravity and piston flow inside said reactor. a) passing at least a portion of the effluent from step a) into a hydroconversion reaction zone comprising at least one three-phase reactor, in the presence of hydrogen, said reactor containing at least one catalytic catalyst bed; hydroconversion and operating as a bubbling bed, with an upward flow of liquid and gas and comprising at least one means for withdrawing said catalyst from said reactor and at least one fresh catalyst booster means in said reactor, under conditions allowing obtain a low carbon content of Conradson Carbon, metals, sulfur and nitrogen.

The present invention therefore aims to provide a process for converting carbonaceous feedstock and preferably heavy hydrocarbon fractions having an initial boiling temperature of at least 300 ° C. into lighter, recoverable products, incorporating a mobile bed technology. and bubbling bed technology, said method for maximizing charge refinement while increasing charge conversion.

Detailed description of the invention.

According to step a) of the process according to the invention, the carbonaceous feed, preferably consisting of a heavy hydrocarbon fraction having an initial boiling point of at least 300 ° C., passes into a reaction zone of hydrorefining comprising at least one moving bed reactor and at least one means for withdrawing said catalyst from said reactor and at least one fresh catalyst booster means in said reactor.

The temperatures are advantageously controlled by hydrogen quenchs arranged between the reactors and / or between the beds of each reactor.

The moving bed technology utilizes a semi-continuous catalyst renewal system by adding fresh catalyst to the top of each reactor and withdrawing used catalyst from the bottom of each reactor. Specific equipment known to those skilled in the art are provided for the reliable transfer of the catalyst under conditions of high temperature and high pressure. Inside the mobile bed reactor or reactors, the catalyst circulates according to the invention, by gravity and piston flow. Spherical catalysts with a diameter of between 0.5 and 6 mm and preferably between 1 and 3 mm are preferably used rather than extruded catalysts to obtain a better flow. During the withdrawal of the used catalyst at the bottom of the reactor, the entire catalytic bed moving in piston flow, moves down a height corresponding to the volume of catalyst withdrawn. The expansion ratio of the catalytic bed operating in a moving bed is advantageously less than 15%, preferably less than 10%, preferably less than 5% and more preferably less than 2%. The rate of expansion is measured according to a method known to those skilled in the art.

According to a very preferred embodiment, the expansion rate of the catalytic bed operating in moving bed is less than 2% and preferably the bed is not expanded. indeed, during the withdrawal of the spent catalyst at the bottom of said reactor, it is the entire bed which moves in downward piston flow, a height corresponding to the volume of catalyst withdrawn. Once the makeup and catalyst removal has been carried out, said reactor behaves like an unexpanded fixed bed.

The spent catalysts, saturated with metals (Ni + V), are advantageously withdrawn at the bottom of the reactors in a moving bed. The hydrorefining step a) of said feedstock is generally carried out under conventional conditions of moving-bed hydrorefining of a liquid hydrocarbon fraction. The operation is usually carried out under an absolute pressure of between 10 and 24 MPa, preferably between 5 and 25 MPa and preferably between 6 and 20 MPa, at a temperature of between 300 and 440 ° C. and preferably between 370 and 410. ° C. The hourly space velocity (WH) and the hydrogen partial pressure are important factors that are chosen according to the characteristics of the product to be treated and the desired conversion. Preferably, the WH is between 0.1 and 4 h -1 and preferably between 0.2 and 2 h -1. The quantity of hydrogen mixed with the feedstock is preferably between 100 and 2000 normal cubic meters (Nm3) per cubic meter (m3) of liquid feed and preferably between 50 and 5000 Nm3 / m3 and very preferably between 200 and 1000 Nm3 / m3. The hydrorefining catalyst used in step a) of the process according to the invention is advantageously a catalyst comprising a support, preferably amorphous and very preferably alumina and at least one metal of group VIII chosen from nickel and cobalt and preferably nickel, said group VIII element being preferably used in combination with at least one Group VIB metal selected from molybdenum and tungsten and preferably the Group VIB metal is molybdenum. Preferably, the hydrorefining catalyst comprises nickel as part of group VIII and molybdenum as part of group VIB. The nickel content is advantageously between 0.5 and 10% by weight of nickel oxide (NiO) and preferably between 1 and 6% by weight and the molybdenum content is advantageously between 1 and 30% by weight. molybdenum trioxide (MoO3), and preferably between 4 and 20% by weight, the percentages being expressed as a percentage by weight relative to the total mass of the catalyst. This catalyst is advantageously in the form of extrudates or beads. This catalyst may also advantageously contain phosphorus and preferably a P205 phosphorus oxide content of less than 20% and preferably less than 10% by weight, the percentages being expressed as a percentage by weight relative to the total mass of the catalyst.

Preferably, the hydrorefining catalyst is in spherical form, with a diameter of between 0.5 and 6 mm and preferably between 1 and 3 mm. The hydrorefining catalyst used in step a) of the process according to the invention advantageously makes it possible to ensure both the demetallation and the desulfurization, under conditions making it possible to obtain a reduced metal, carbon-containing liquid feed. Conradson and sulfur. The reactors in a moving bed advantageously operate either in the downward flow of fluids (down-flow mode according to the English terminology), in this case, step a) of the process according to the invention is advantageously carried out in the Shell process conditions with Bunker type reactors described in Scheffer et al. 1998, or upstream cocurrent rising fluids also called countercurrent (up-flow mode according to English terminology), wherein the catalyst flows from the top to the bottom of the reactor and the reaction fluids flow from the bottom to the top of the reactor against the catalyst flow. In the second case, step a) of the process according to the invention is advantageously carried out under the conditions of the process described in Reynolds B.E., Bachtel R.W., Yagi K. (1992) Chevron's onstream catalyst replacement (OCR). NPRA meeting New Orleans.

According to step b) of the process according to the invention, at least a portion and preferably all of the effluent from step a) passes into at least one triphasic reactor, in the presence of hydrogen, said reactor containing at least one hydroconversion catalyst and operating as a bubbling bed, with an upward flow of liquid and gas and comprising at least one means for withdrawing said catalyst from said reactor and at least one fresh catalyst booster means in said reactor, under conditions allowing to obtain a reduced carbon Conradson content liquid filler, metals, sulfur and nitrogen.

The mixture of hydrocarbon liquid and ascending hydrogen gas advantageously passes over a bed of catalytic particles at such a rate that the catalytic particles are subjected to forced random movement while the liquid and the gas pass through the bed from bottom to top. The flow rate of the mixture and in particular the gas flow rate causes the expansion of the catalytic bed. The expansion rate of the catalytic bed in a reactor operating in a bubbling bed is advantageously greater than 30%, the expansion ratio being measured by a method known to those skilled in the art.

Furthermore, bubbling bed technology being widely known, only the main operating conditions will be repeated here. Step b) of hydroconversion of said effluent from step a) of the process according to the invention is generally carried out under standard bubbling bed hydroconversion conditions of a liquid hydrocarbon fraction. The operation is usually carried out under an absolute pressure of between 2 and 35 MPa, preferably between 5 and 25 MPa, and preferably between 6 and 20 MPa, at a temperature of between 300 and 550 ° C. and preferably between 350 and 500. ° C. The hourly space velocity (WH) and the hydrogen partial pressure are important factors that are chosen according to the characteristics of the product to be treated and the desired conversion. Preferably, the WH is between 0.1 h -1 and 10 h -1 and preferably between 0.15 h -1 and 5 h -1. The quantity of hydrogen mixed with the feedstock is preferably between 50 and 5000 normal cubic meters (Nm3) per cubic meter (m3) of liquid feed and preferably between 100 and 2000 Nm3 / m3 and very preferably between 200 and 1000 Nm3 / m3.

The catalysts used are widely marketed. These are granular catalysts whose size is of the order of 1 mm or less. The hydroconversion catalyst used in stage b) of the process according to the invention is advantageously a catalyst comprising a support, preferably amorphous and very preferably alumina and at least one metal of group VIII chosen from nickel and cobalt and preferably nickel, said group VIII element preferably being used in combination with at least one Group VIB metal selected from molybdenum and tungsten and preferably the Group VIB metal is molybdenum.

Preferably, the hydroconversion catalyst comprises nickel as part of group VIII and molybdenum as part of group VIB. The nickel content is advantageously between 0.5 and 10% expressed by weight of nickel oxide (NiO) and preferably between 1 and 6% by weight and the molybdenum content is advantageously between 1 and 30% expressed by weight of molybdenum trioxide (MoO3), and preferably between 4 and 20% by weight. This catalyst is advantageously in the form of extrudates or beads. This catalyst may also advantageously contain phosphorus and preferably a content of phosphorus oxide P2O5 less than 20% and preferably less than 10% by weight. Preferably, the catalyst is in the form of extrudates or beads.

The hydroconversion catalyst used according to the process according to the invention can be partially replaced by fresh catalyst by withdrawal, preferably at the bottom of the reactor and by introducing, either at the top or at the bottom of the reactor, fresh or regenerated catalyst or rejuvenated, preferably at regular time interval and preferably by puff or almost continuously. The replacement rate of the spent hydroconversion catalyst with fresh catalyst is advantageously between 0.05 kilograms and 10 kilograms per cubic meter of treated feedstock, and preferably between 0.3 kilograms and 3 kilograms per cubic meter of feedstock treated. This withdrawal and replacement are performed using devices advantageously allowing the continuous operation of this hydroconversion step. The unit usually comprises a recirculation pump for maintaining the bubbling bed catalyst by continuously recycling at least a portion of the liquid withdrawn at the top of the reactor and reinjected at the bottom of the reactor. It is also advantageously possible to send the spent catalyst withdrawn from the reactor into a regeneration zone in which the carbon and the sulfur contained therein are removed and then to return this regenerated catalyst to the hydroconversion stage b). It is also advantageously possible to send the spent catalyst withdrawn from the reactor to a rejuvenation zone in which the major part of the deposited metals is removed before sending the spent and recycled catalyst to a regeneration zone in which the carbon is removed. and the sulfur contained therein and return this regenerated catalyst in step b) of hydroconversion.

Step b) of the process according to the invention is advantageously carried out under the conditions of the H-OIL process as described for example in US-A-4521295 or US-A-4495060 or US-A-4457831 or US-A-4354852 or in the article Aiche, March 19-23, 1995, HOUSTON, Texas, paper number 46d, second generation ebullated bed technology.

The hydroconversion catalyst used in step b) advantageously makes it possible to obtain a high conversion to light products, that is to say in particular in the gasoline and diesel fuel fractions.

Step b) is advantageously carried out in one or more three-phase hydroconversion reactors. An inter-reactor hydrogen gas quench is advantageously implemented between the hydrorefining reaction zone of step a) and the hydroconversion reaction zone of step b) so as to adjust the temperature at the inlet. of the reactor (s).

The effluent from step b) of the process according to the invention and preferably from the last bubbling bed reactor is advantageously sent to at least one separator in series. The liquid fractions from these separators are then advantageously sent to a steam stripping column. The stripped effluent is then in turn advantageously sent to an atmospheric fractionation column and then under vacuum to separate it into several sections: naphtha, middle distillate, vacuum distillate and vacuum residue.

Description of Figure 1. Figure 1 illustrates the invention in a preferred embodiment. The charge consisting of a heavy hydrocarbon fraction having an initial boiling point of at least 300 ° C is sent via line (1) to a hydrorefining reaction zone comprising a moving bed reactor (2). reactor comprising means for withdrawing said catalyst from said reactor via the pipe (4) and at least one fresh catalyst booster means in said reactor via the pipe (3). The effluent obtained at the end of the hydrorefining stage (exiting via line 5) is then sent to a hydroconversion reaction zone (6) comprising a triphasic reactor operating as a bubbling bed. An additional fresh catalyst is added to the catalyst bed in the bubbling bed reactor via line (7), and an equivalent amount of used catalyst is withdrawn from said reactor via line (8). The effluent from the hydroconversion reaction zone (6) is then sent to a series separator (10) via the pipe (9). The liquid fraction from the separator is then sent via line (11) to a stripping column (12) with steam. The stripped effluent is then in turn sent via line (13) into an atmospheric fractionation and vacuum column (14) to separate it into several sections: naphtha (15), middle distillate (16), distillate sub- void (17) and vacuum residue (18).

Example: The examples illustrate the invention without limiting its scope.

Comparative Example: Treatment of a vacuum residue type in a conventional bubbling bed process.

The feed is an extra heavy duty vacuum residue (RSV) whose properties are as follows:

Table 1: Characteristics of the specific gravity load (API 8.30 Gravity) Nitrogen% wt 0.449 Sulfur, wt% 2.944 Conradson Carbon% wt 17.17 C7 Asphaltene% wt 6.0 Nickel, ppm 75 Vanadium, ppm 262 The feed is sent entirely in one unit hydroconversion in the presence of hydrogen, said section comprising two triphasic reactors containing two hydroconversion catalysts NiMo / alumina having a NiO content of 3% by weight and a MoO3 content of 10% by weight, the percentages being expressed relative to the total mass of the catalyst. The section operates as a bubbling bed operating with an upward flow of liquid and gas. The unit has two bubbling bed reactors in series and is equipped with an inter-floor separator.

The conditions applied in the hydroconversion unit are the following: Tables 2: operating conditions applied in the two bubbling bed reactors Boiler bed T 1st reactor, ° C 421 T 2nd reactor, ° C 426 Catalyst replacement rate, kg / t 1.36 Quantity of hydrogen mixed with the feed, Nm3 / m3 424 VVH (reactor), hr-1 0.247 VVH (catalyst), hr-1 0.394 The effluent resulting from the hydroconversion process using a reaction zone The hydroconversion method comprising two ebullated bed reactors in series is characterized and the properties of the hydrocarbon fraction obtained are given in Table 3. Tables 3: Characteristics of the hydrocarbon fraction obtained Conversion% wt 65.61 H2 Consumption,% wt 1.479 HDN,% wt 39.18 HDS,% wt 82.41 HDAs,% wt 48.65 HDCCR,% wt 53.62 HDNi, wt% 80.20 HDV, wt% 87.71 Example according to the invention.

The feedstock described in the previous example is sent entirely to a hydrorefining reaction zone (step a) comprising a moving bed reactor comprising a NiMo / alumina hydrotreatment catalyst having a NiO content of 3% by weight and a content of in MoO 3 of 10% by weight, the percentages being expressed relative to the total mass of the catalyst.

The effluent from step a) is sent entirely in a hydroconversion step b) in the presence of hydrogen, said section comprising a three-phase reactor containing a NiMo / alumina hydroconversion catalyst having a NiO content of 3. % weight and a MoO3 content of 10% by weight, the percentages being expressed relative to the total mass of the catalyst. the section operates as a bubbling bed with an upward flow of liquid and gas.

The conditions applied in the hydrorefining unit (step a) and in the hydroconversion section (step b) are as follows: Tables 4: operating conditions applied in the hydrorefining and hydroconversion unit (step a) and b) Mobile bed T 1st reactor (step a), ° C 395 T 2nd reactor (step b), ° C 440 Catalyst replacement rate, kg / t 0.56 Quantity of hydrogen mixed with the feedstock, 483 Nm3 / m3 WH (reactor), hr-1 0.247 WH (catalyst), hr-1 0.306 The effluent from the process according to the invention using a mobile bed hydrorefining reaction zone followed by a hydroconversion section in ebullition bed is characterized and the properties of the hydrocarbon fraction obtained are given in Table 5. Tables 5: Characteristics of the hydrocarbon fraction obtained Conversion 1st reactor% wt 66.40 Conversion 2nd reactor% wt 65.61 H2 Consumption,% wt 1.481 H2, Nm3 / m3 166 HDN,% wt 41.73 HDS,% wt 8 2.40 HDAs,% wt 66.24 HDCCR,% wt 54.83 HDNi,% wt 90.01 HDV, wt% 93.52 It is thus seen that the process according to the invention using a mobile bed hydrorefining reaction zone followed by a section of Boiler bed hydroconversion provides a hydrocarbon effluent with lower levels of nitrogen, asphaltenes and metals than a conventional prior art process while maintaining high conversion levels and much lower catalyst consumption. 15

Claims (14)

REVENDICATIONS1. A process for converting carbonaceous feedstocks into more valuable lighter products, said process having the following steps: a) passing said feedstock into a hydrorefining reaction zone comprising at least one moving bed reactor comprising at least one catalytic catalyst catalyst bed; hydrorefining and at least one means for withdrawing said catalyst from said reactor and at least one fresh catalyst booster means in said reactor, said catalyst circulating by gravity and piston flow inside said reactor, b) passing through at least a portion of the effluent from step a) in a hydroconversion reaction zone comprising at least one three-phase reactor, in the presence of hydrogen, said reactor containing at least one catalytic bed of hydroconversion catalyst and operating in ebullating bed, with an upward flow of liquid and gas and comprising at least one means for withdrawing said catalyst from said reactor and at least one fresh catalyst booster means in said reactor, under conditions to obtain a reduced Conradson Carbon content liquid feedstock, metals, sulfur and nitrogen. The process according to claim 1 wherein the feeds are heavy hydrocarbon fractions having a sulfur content of at least 0.5%, preferably at least 1%, a Conradson carbon content of at least 3% wt., A metal content of at least 20 ppm and an initial boiling temperature of at least 300 ° C, and a final boiling temperature of at least 500 ° C. 3. Method according to one of claims 1 or 2 wherein the charges are atmospheric residues corresponding to a 380 ° C + cut, vacuum residues corresponding to a cut 560 ° C + and deasphalted oils (DAO) corresponding to a cut 560 ° C + lighter. 4. Method according to one of claims 1 to 3 wherein the hydrorefining catalyst used in step a) is a spherical catalyst with a diameter of between 0.5 and 6 mm. 5. Method according to one of claims 1 to 4 wherein the expansion rate of the catalytic bed operating in moving bed is less than 15%. 6. The method of claim 5 wherein the expansion rate of the catalytic bed operating in a moving bed is less than 2%. 7. Method according to one of claims 1 to 6 wherein the hydrorefining catalyst used in step a) is a catalyst comprising an amorphous support and at least one group VIII metal selected from nickel and cobalt, said Group VIII element being used in combination with at least one Group VIB metal selected from molybdenum and tungsten. 8. Method according to one of claims 1 to 7 wherein the hydrorefining step a) operates under an absolute pressure of between 10 and 24 MPa, at a temperature between 300 and 440 ° C at a space velocity ( WH) of between 0.1 and 4 h -1 and a quantity of hydrogen mixed with the feed of between 100 and 2000 normal cubic meters (Nm3) per cubic meter (m3) of liquid feed. 9. Method according to one of claims 1 to 8 wherein the moving bed implemented in step a) operates downward co-flow fluids. 10. Method according to one of claims 1 to 8 wherein the moving bed implemented in step a) operates against the current. 11. Method according to one of claims 1 to 10 wherein the hydroconversion catalyst used in step b) is a catalyst comprising an amorphous support and at least one group VIII metal selected from nickel and cobalt, said Group VIII element being used in combination with at least one Group VIB metal selected from molybdenum and tungsten. 12. Process according to one of claims 1 to 11, in which the hydroconversion catalyst comprises nickel as element of group VIII and molybdenum as element of group VIB, the nickel content being between 0, 5 to 10% by weight of nickel oxide (NiO) and the molybdenum content being between 1 and 30% by weight of molybdenum trioxide (MoO3). 13. Method according to one of claims 1 to 12 wherein the expansion rate of the catalytic bed operating bubbling bed is greater than 30%. 14. Method according to one of claims 1 to 13 wherein the hydroconversion step b) operates at an absolute pressure of between 2 and 35 MPa, at a temperature between 300 and 550 ° C at a WH between 0.1 h-1 and 10 h-1 and a quantity of hydrogen mixed with the feed of between 50 and 5000 normal cubic meters (Nm3) per cubic meter (m3) of liquid feed. 10